Replace case or replace drives?

[Simpleone71]

Sorry about the title, I went ahead and bought the bigger case, so I just removed the part about whether to buy the case or new drives and left the scenario where I did buy the case.



I am currently running:
Supermicro CSE-825TQ-563LPB 8-Bays
Supermicro X10SRI-F-O
Intel Xeon E5-2630v3
64 GB ECC ram
8 HGST Deskstar NAS 4TB drives in Raidz2
M1015 flashed as LSI in IT mode

I have purchased a Supermicro CSE-846E16-R1200B 24 bay case and will be moving all the hard drives and hardware to the new case.

My questions are:

1) This is as easy as moving everything over and then just import the vdev or something similiar?
2) I have four 4 TB Seagate NAS 5900 rpm drives in another box. The eight in this server are HGST 7200rpm drives. Is it possible for me to create a new vdev with the slower drvies since they are on a different vdev or should I always match all my drives in the server to the 7200 rpm.

 

[Robert Trevellyan]

I think you may be confused about the difference between a vdev and a pool.

1. Yes, it's as easy as moving everything over. No need to import anything if you're using the same boot device. If you manually configured the network settings, you might have to redo those.
2. The performance of your pool will tend to be limited by the lowest performing individual devices. Whether that matters is up to you. I believe this effect will be reduced if each vdev is made of matched devices.

 

[Simpleone71]

I was getting the two mixed up. That's great on item #1, I will be using the same usb boot device.

On the other item, so if I leave my original eight 7200rpm drives in their own zpool, create a new vdev and zpool for the new eight 5900rpm drives, that would leave the speed of the original zpool like it was? Or does Freenas somehow tie all drives together even if they are in different vdevs and zpools?

 

[joeschmuck]

The pools will run at separate speeds if you want to think about them that way, they are not dependent on each other.

 

[Simpleone71]

Great, Thanks!

 

[Robert Trevellyan]

Further, if you were to add the 2nd vdev to the original pool, ZFS would try to balance the load between them based on their relative write performance. I assume this could potentially lead to lower or higher overall performance, depending on workload and other factors.

 

[Simpleone71]

Sounds like keeping them seperate is the way to go. I don't mind that as, I'll probably use the 5900rpm drive zpool as a backup spot for my server. From what I've researched they'll still saturate the 1 gb link of the nic

 

[Robert Trevellyan]

they'll still saturate the 1 gb link of the nic

Yes, they will.

 

[joeschmuck]

Saturate within reasonable limits. Depending on the operation at hand, you can achieve 100MB/sec rates say for large file transfers but lots of small files will have additional overhead and just not give you the full saturation that everyone would really like. I'm certain I could saturate a 10Gb NIC, if I had a few 10Gb NIC cards laying around. Something like that is not realistic for me yet, I'd rather spend my money on the next set of hard drives I need to buy. I want two 7TB SSDs [or larger] but maybe someone could send me a pair for "evaluation" and it may take me a few years to evaluate them properly.

 

[anodos]

Saturate within reasonable limits. Depending on the operation at hand, you can achieve 100MB/sec rates say for large file transfers but lots of small files will have additional overhead and just not give you the full saturation that everyone would really like. I'm certain I could saturate a 10Gb NIC, if I had a few 10Gb NIC cards laying around. Something like that is not realistic for me yet, I'd rather spend my money on the next set of hard drives I need to buy. I want two 7TB SSDs [or larger] but maybe someone could send me a pair for "evaluation" and it may take me a few years to evaluate them properly.

Based on what I've observed on linustechtips, there's an inverse relationship between reviewer intelligence and quality of equipment vendors give for evaluation.

 

[joeschmuck]

I'm more than happy to look like an idiot if that means I get a pair of 7TB (or larger) SSDs, after all linustechtips can do it, then so can I.

 

[anodos]

I'm more than happy to look like an idiot if that means I get a pair of 7TB (or larger) SSDs, after all linustechtips can do it, then so can I.

Unfortunately, some people have an innate talent for being an idiot that cannot be faked.